﻿// Copyright 2009-2024 Josh Close
// This file is a part of CsvHelper and is dual licensed under MS-PL and Apache 2.0.
// See LICENSE.txt for details or visit http://www.opensource.org/licenses/ms-pl.html for MS-PL and http://opensource.org/licenses/Apache-2.0 for Apache 2.0.
// https://github.com/JoshClose/CsvHelper
using System.Collections;
using System.Diagnostics;
using System.Linq.Expressions;
using System.Reflection;

namespace CsvHelper.Configuration;

/// <summary>
/// A collection that holds <see cref="MemberReferenceMap"/>'s.
/// </summary>
[DebuggerDisplay("Count = {list.Count}")]
public class MemberReferenceMapCollection : IList<MemberReferenceMap>
{
	private readonly List<MemberReferenceMap> list = new List<MemberReferenceMap>();

	/// <summary>Gets the number of elements contained in the <see cref="T:System.Collections.Generic.ICollection`1" />.</summary>
	/// <returns>The number of elements contained in the <see cref="T:System.Collections.Generic.ICollection`1" />.</returns>
	public virtual int Count => list.Count;

	/// <summary>Gets a value indicating whether the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only.</summary>
	/// <returns>true if the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only; otherwise, false.</returns>
	public virtual bool IsReadOnly => false;

	/// <summary>Gets or sets the element at the specified index.</summary>
	/// <returns>The element at the specified index.</returns>
	/// <param name="index">The zero-based index of the element to get or set.</param>
	/// <exception cref="T:System.ArgumentOutOfRangeException">
	/// <paramref name="index" /> is not a valid index in the <see cref="T:System.Collections.Generic.IList`1" />.</exception>
	/// <exception cref="T:System.NotSupportedException">The member is set and the <see cref="T:System.Collections.Generic.IList`1" /> is read-only.</exception>
	public virtual MemberReferenceMap this[int index]
	{
		get => list[index];
		set => list[index] = value;
	}

	/// <summary>Returns an enumerator that iterates through the collection.</summary>
	/// <returns>A <see cref="T:System.Collections.Generic.IEnumerator`1" /> that can be used to iterate through the collection.</returns>
	/// <filterpriority>1</filterpriority>
	public virtual IEnumerator<MemberReferenceMap> GetEnumerator()
	{
		return list.GetEnumerator();
	}

	/// <summary>Returns an enumerator that iterates through a collection.</summary>
	/// <returns>An <see cref="T:System.Collections.IEnumerator" /> object that can be used to iterate through the collection.</returns>
	/// <filterpriority>2</filterpriority>
	IEnumerator IEnumerable.GetEnumerator()
	{
		return GetEnumerator();
	}

	/// <summary>Adds an item to the <see cref="T:System.Collections.Generic.ICollection`1" />.</summary>
	/// <param name="item">The object to add to the <see cref="T:System.Collections.Generic.ICollection`1" />.</param>
	/// <exception cref="T:System.NotSupportedException">The <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only.</exception>
	public virtual void Add(MemberReferenceMap item)
	{
		list.Add(item);
	}

	/// <summary>Removes all items from the <see cref="T:System.Collections.Generic.ICollection`1" />.</summary>
	/// <exception cref="T:System.NotSupportedException">The <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only. </exception>
	public virtual void Clear()
	{
		list.Clear();
	}

	/// <summary>Determines whether the <see cref="T:System.Collections.Generic.ICollection`1" /> contains a specific value.</summary>
	/// <returns>true if <paramref name="item" /> is found in the <see cref="T:System.Collections.Generic.ICollection`1" />; otherwise, false.</returns>
	/// <param name="item">The object to locate in the <see cref="T:System.Collections.Generic.ICollection`1" />.</param>
	public virtual bool Contains(MemberReferenceMap item)
	{
		return list.Contains(item);
	}

	/// <summary>Copies the elements of the <see cref="T:System.Collections.Generic.ICollection`1" /> to an <see cref="T:System.Array" />, starting at a particular <see cref="T:System.Array" /> index.</summary>
	/// <param name="array">The one-dimensional <see cref="T:System.Array" /> that is the destination of the elements copied from <see cref="T:System.Collections.Generic.ICollection`1" />. The <see cref="T:System.Array" /> must have zero-based indexing.</param>
	/// <param name="arrayIndex">The zero-based index in <paramref name="array" /> at which copying begins.</param>
	/// <exception cref="T:System.ArgumentNullException">
	/// <paramref name="array" /> is null.</exception>
	/// <exception cref="T:System.ArgumentOutOfRangeException">
	/// <paramref name="arrayIndex" /> is less than 0.</exception>
	/// <exception cref="T:System.ArgumentException">The number of elements in the source <see cref="T:System.Collections.Generic.ICollection`1" /> is greater than the available space from <paramref name="arrayIndex" /> to the end of the destination <paramref name="array" />.</exception>
	public virtual void CopyTo(MemberReferenceMap[] array, int arrayIndex)
	{
		list.CopyTo(array, arrayIndex);
	}

	/// <summary>Removes the first occurrence of a specific object from the <see cref="T:System.Collections.Generic.ICollection`1" />.</summary>
	/// <returns>true if <paramref name="item" /> was successfully removed from the <see cref="T:System.Collections.Generic.ICollection`1" />; otherwise, false. This method also returns false if <paramref name="item" /> is not found in the original <see cref="T:System.Collections.Generic.ICollection`1" />.</returns>
	/// <param name="item">The object to remove from the <see cref="T:System.Collections.Generic.ICollection`1" />.</param>
	/// <exception cref="T:System.NotSupportedException">The <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only.</exception>
	public virtual bool Remove(MemberReferenceMap item)
	{
		return list.Remove(item);
	}

	/// <summary>Determines the index of a specific item in the <see cref="T:System.Collections.Generic.IList`1" />.</summary>
	/// <returns>The index of <paramref name="item" /> if found in the list; otherwise, -1.</returns>
	/// <param name="item">The object to locate in the <see cref="T:System.Collections.Generic.IList`1" />.</param>
	public virtual int IndexOf(MemberReferenceMap item)
	{
		return list.IndexOf(item);
	}

	/// <summary>Inserts an item to the <see cref="T:System.Collections.Generic.IList`1" /> at the specified index.</summary>
	/// <param name="index">The zero-based index at which <paramref name="item" /> should be inserted.</param>
	/// <param name="item">The object to insert into the <see cref="T:System.Collections.Generic.IList`1" />.</param>
	/// <exception cref="T:System.ArgumentOutOfRangeException">
	/// <paramref name="index" /> is not a valid index in the <see cref="T:System.Collections.Generic.IList`1" />.</exception>
	/// <exception cref="T:System.NotSupportedException">The <see cref="T:System.Collections.Generic.IList`1" /> is read-only.</exception>
	public virtual void Insert(int index, MemberReferenceMap item)
	{
		list.Insert(index, item);
	}

	/// <summary>Removes the <see cref="T:System.Collections.Generic.IList`1" /> item at the specified index.</summary>
	/// <param name="index">The zero-based index of the item to remove.</param>
	/// <exception cref="T:System.ArgumentOutOfRangeException">
	/// <paramref name="index" /> is not a valid index in the <see cref="T:System.Collections.Generic.IList`1" />.</exception>
	/// <exception cref="T:System.NotSupportedException">The <see cref="T:System.Collections.Generic.IList`1" /> is read-only.</exception>
	public virtual void RemoveAt(int index)
	{
		list.RemoveAt(index);
	}

	/// <summary>
	/// Finds the <see cref="MemberReferenceMap"/> using the given member expression.
	/// </summary>
	/// <typeparam name="T">The <see cref="System.Type"/> the member is on.</typeparam>
	/// <param name="expression">The member expression.</param>
	/// <returns>The <see cref="MemberReferenceMap"/> for the given expression, or null if not found.</returns>
	public virtual MemberReferenceMap? Find<T>(Expression<Func<T, object>> expression)
	{
		var member = ReflectionHelper.GetMember(expression);
		return Find(member);
	}

	/// <summary>
	/// Finds the <see cref="MemberReferenceMap"/> using the given member.
	/// </summary>
	/// <param name="member">The member.</param>
	/// <returns>The <see cref="MemberReferenceMap"/> for the given expression, or null if not found.</returns>
	public virtual MemberReferenceMap? Find(MemberInfo member)
	{
		var existingMap = list.SingleOrDefault(m =>
			m.Data.Member == member ||
			m.Data.Member.Name == member.Name &&
			(
				m.Data.Member.DeclaringType!.IsAssignableFrom(member.DeclaringType) ||
				member.DeclaringType!.IsAssignableFrom(m.Data.Member.DeclaringType)
			)
		);

		return existingMap;
	}
}
